Removable top for soaking pits



' Patented June 27, 1939 2,103,121 REMOVABLE 'ror son soAnrNo rrrsWilliam Dean, Gary, ma. Original application October 12, 1936, SerialNo.

Divided and this application May 17,

1937, Serial No. 143.220 4 3 Claims. (cl. 288-10) This application is adivision of my application Serial No; 105,336, filed ,.0ctober 12, 1936,for Soaking pits and like heating furnaces, and the invention relatesspecifically to covers or doors for said pits and the means forretracting the same.

Retractable covers or doors as heretofore builtv leave much to bedesired in point of life and insulation. Where such covers are supportedby a truck carried on rails along the'side of the pit,

sumcieht space for overlap is lacking; the view or the pit by thecra'neman is limited; and high cover and pit top repairs follow.Wherefthe covers are carried on trucks, it is impossible to secure goodsealing because, if the cover be lowered to seat well, the weight is oi!the axles and no traction remains. Unless covers are well sealed, theypermit serious heat losses as well as infiltration at times and damageto the cover edgecastings and channeling vofpit tops. For small pits,covers may be made with a cast steel frame lined with a sphericallyshaped arch of fire brick. For large pits, however, it is necessary touse structural cover frames, for which 2 spherical arches are notsuitable because of the difllculty of providing for the arch thrusts andbecause of the volume of space formed beneath such arches. This hasforced the-useof flat or ,suspended arches of refractory units,supported by special hanger castings that rest upon the structural framemembers. This type of cover is expensive in first cost and short livedbecause there is no means of keeping the brick elements tight, andfurther insulation cannot be applied as the hanger vcastings becomesoverheated. The racking of such-covers due to movements accentuate thedifllculties.

One object of the present invention is to provide. a multiple archedcover which will afford a readyaccess to recuperators for inspection andcleaning and which may be insulated; also a cover that will remain tightin spite of, movements, reducethe number of special brick shapes 1required, and eliminate hanger castings sus-,- ceptible to damage byheat.

Other objects are to provide means for lowering and sealing covers onpit tops; to avoidthe use of retracting mechanism in hot zones; and

" to eliminate hydraulic cover operating mechi Inthe accompanyingdrawing-- Figures '1 and 2 are, respectively, a vertical longitudinalsection of a portion of t h e pit, and a top plan view of the sametogether'with its as portable cover andthe carriage through means ofwhich the said cover is transferred from open to closed position; and

Figure 3 is a detail sectional view, on an enlarged scale, of one of theintermediate suspending skews employed in the cover organization 5 shownin Fi ure 1.

Referring to Figure 1 which shows a partial sectional elevation of asoaking pit with an improved cover II, to Figure 2 which shows a partialplan view of same, and to Figure 3 which 10 shows a section through oneof the intermediate skew backs 28b and alloy supports for said cover,the cover comprises a series of short arches 28a across the shortdimension of the cover. The end skew backs 280' are supported by the end15 frames "list each end and by suspended alloy bars Be at intermediatepoirits. The arch thrust is taken by the side frames of the coversupple- .meiited by a heavy central arch tie rod 28f. The

skews] are made from first quality fire brick and are the only specialshapes required. The arch brick 38a may be standard 9" brick or may be2500 degree insulating brick, requiring no extrar'ieous insulation andgreatly reducing the total weight of a cover. If standard fire brickarches be, used. additional insulation may be added withoutfear ofdestroying the supporting hangers. As shown in Figure v3, skews 28b aremade in two mated parts that embrace the alloy hanger bar 28c, whilecopper radiator bar 289 is welded 30 to the alloy hanger bar between thesupporting alloy bolts 2th and projects above the brick skews forexposure to atmosphere in giving oil its heat and preventing overheatingof the alloy bar which is entirely surrounded by brick. O In practice,the alloy bar is rolled from chrome-nickel 1 (18/8) one and one-half bytwo inches and the radiator bar is one-quarter inch by six inches.

1 The cover frame comprises structural channels and beams Hi with barcross bracing Illa 0 (Figure 2), all securely welded. A series of simplesteel or alloy castings 28L along the ends, bolted to the frame members,support the end skews 2.0, while similar castings along the sidessupport standard flre brick blocks 28m and close the ends of the crossarches. v The completed cover is supported pivotally on its transversecenter line from a pair of cantilevers 2! extending from a truck 30placed at one end of the pit,'as shown. The truck is providedwith fourwheels "a, Ilb, keyed to axles 30c and partially counterweighted andactuated by a motor drive comprising a motor 3i, reducer {la andchaindrive lib to one rear axle 30c. Wham-the cover is in place asshown, its weight 5 June 27, 1939.

I w. T. DEAN REMOVABLE TOP FOR SOAKING PITS Original Filed Oct. 12, 1936v Jzuemi'on fflam: I @244 r RI E .INIIIIIIII 'r A.

